In a shared disk database system, locks are typically owned by a central entity which either owns all of the locks or a distributed lock ownership where each member in the shared disk cluster owns a certain portion of the locks. The owning entity for a lock is responsible for giving the lock out to any cluster member requiring the lock.
The amount of communications required to obtain a lock from the lock owner can significantly impact the performance of any shared disk system. Each message requires processing and network bandwidth consumption, as well as contributing to overall system throughput. Reducing the number of messages would in turn reduce the consumption of these resources.